216868556 has 6 divisors (see below), whose sum is σ = 379519980. Its totient is φ = 108434276.

The previous prime is 216868537. The next prime is 216868559. The reversal of 216868556 is 655868612.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 216868556.

It is not an unprimeable number, because it can be changed into a prime (216868559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27108566 + ... + 27108573.

It is an arithmetic number, because the mean of its divisors is an integer number (63253330).

Almost surely, 2^216868556 is an apocalyptic number.

It is an amenable number.

216868556 is a deficient number, since it is larger than the sum of its proper divisors (162651424).

216868556 is a wasteful number, since it uses less digits than its factorization.

216868556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54217143 (or 54217141 counting only the distinct ones).

The product of its digits is 691200, while the sum is 47.

The square root of 216868556 is about 14726.4576867623. The cubic root of 216868556 is about 600.8031429744.

The spelling of 216868556 in words is "two hundred sixteen million, eight hundred sixty-eight thousand, five hundred fifty-six".